George a



G. A. SEIB.

TYPEWRITING MACHINE.

APPLICATION FILED 050.4.1919.

1,375,]. 1 3B Patented Apr. 19, 1921.

INVENTUR P $1,1 2 A7 %ZM M Hi5 ATTURNEY UNITED STATES PATENT ()FFICE.

GEORGE A. SEIB, or ILION, NEW Yong, ASSIGNOR 'ro REMINGTON TYPEWRITER COMPANY, or ILroN, NEW YORK, A CORPORATION on NEW YORK.

TYPEWRITING-MACHINE.

Application filed December 4, 1.919.

To all whom it may concern:

Be it known that I, GEORGE A. SEIB, a citizen of the United States, and resident of Ilion, in the county of Herkimer and State of New York, have invented certain new and useful Improvements in Typewriting- Machines, of which the following is a specification.

My present invention relates to pivot wire tightening devices for typewriting machines, and its object is to provide means for maintaining the pivot wire securely fixed to its support or bearing so that said wire will not be displaced accidentally or during the actuation of the type bars.

In typewriting machines in which the type bars are mounted on a pivot or fulcrum wire, the wire is usually arranged in a slot formed in the type bar segment. I is necessary in practice that the wire fit loosely enough to enable it to be readily inserted and removed from its slot or bearing, and at the same time that the wire be so secured when in place that it shall provide a fixed bearing for the type bars. In carrying out my pre ent invention I provide devices in the form of plates which are secured to the top of the segment, said plates having openings or engaging devices which cooperate directly with the ends of the pivot wire, which ends are properly shaped to engage with the plates. The function of the plates is to force or press the wire downward against the lower or longer side wall of its slotway or hearing, the construction being such that this pressure is sufiicient to hold the wire fixed but it is not excessive and hence there is no liability of distorting the wire itself or its support.

To the above and other ends which will hereinafter appear, myv invention consists in the features of construction, combinations of devices, and arrangements of parts hereinafter described and particularly pointed out in the claims.

The invention will be described and explained in detail in connection with the following drawings wherein- Figure 1 is a fragmentary front to rear sectional view of the type action, mounting and associate parts of a typewriting machine embodying the preferred form of the invention.

Specification of Letters Patent.

Patented Apr. 19, 1921.

Serial No. 342,385.

Fig. 2 is a front elevation of the type bar segment.

3 is an enlarged fragmentary plan view showing one end of the segment with the pressure plate mounted thereon, the head of the tightener or screw being sectioned away.

Fig. 4 is an enlarged fragmentary front view of one end of the segment, parts being broken away.

5 is a fragmentary perspective view of one end of the segment.

6 is a fragmentary front View of one end of the segment, showing the pressure plate before pressure from the screw tightener has been applied thereto.

Referring to Figs. 1 and 2, which illustrate a typewriting machine of the general character of the machine disclosed more fully in the patent granted to Oscar Woodward, June 8, 1920, No. 1,342,489, 1 designates the top plate to which is suitably se' cured a vertically disposed type bar support or segment 2 provided with a series of radial slots 3 in which are arranged front strike type bars 4. Said type bars are perforated so that they may be pivoted on a common pivot wire 5 which passes through the per forations and is supported on the segment. The free ends of the set of type bars are normally supported on a type rest 6 and are adapted to strike against the front face of a platen 7, said type bars cooperating when in printing position with a center guide 8 fixed to the type bar support or segmental plate 2. The heel portions of the type bars are provided with slots 9 with which engage headed pins 10, each pin projecting laterally from the upper end of the long arm of a lever 11 having a stationary pivot 12, the short horizontally disposed arm of said lever 11 being connected by a link 13 with a key lever 14, the set of key levers being arranged within the base portion 15 of the main frame. 5

The pivot wire 5 is curved to conform to the arc of a circle as usual and is seated in a bearing that is correspondingly curved or arcuate, said bearing being a slot or groove 16 cut into the rear face of the segment plate 2. As will be clearly apparent from Figs. 1 and 2, the slot 16 is formed near the bottom or outer curved face of the segment so that the fulcrum wire when seated in said slot extends through and transversely of the radial slots 3 in which the type bars are arranged. The upper wall 16 and the opposite lower wall 16 of the slot are slightly curved as shown in Fig. 3 in correspondence with the circular cross section of the pivot wire, and the dimensions are such that the pivot wire may be readily slid in and out of the slotway 16 from either end but the diameter of the pivot wire is greater than the rear open side of the slot.

As has been stated, it is desirable after the pivot wire has been slid into place in its slot or bearing to secure it in fixed position so that it will provide a fixed center of rotation for the type bars, and to this end I provide pivot wire tightener devices which may cooperate with each end portion of the pivot wire although in some cases it may not be necessary or desirable to provide two sets of such devices. The set of tightening devices at each end of the segment comprises an elastic or resilientelement in the form of a plate 17 made preferably of sheet metal of suflicient thickness to give considerable stifiness but at the same time capable of yielding to some extent. his elastic or resilient element or plate is shaped to conform generally to the top of the end portion of the segment and is formed with an elongated slot 18 which receives a headed screw 19. The shank of this screw passes down loosely through the opening 18 and engages in a tapped hole 20 formed in the top of the segment, the hole being of such depth that the point of the screw does not touch the bottom of the hole when the screw is fully screwed in until the bottom of its head engages with and is arrested by the top of the plate 17 surrounding the hole 18. This screw is the pivot wire tightener proper and also performs the additional function of securing the elastic element or plate 17 to the support or segment 2. The pivot wire 5 projects somewhat above the top of the segment and its end 5 is coned or pointed. The outer end portion of the plate 17 is shaped to cooperatively engage with this coned end 5 of the pivot wire. In the present instance the engaging device is provided by forming a hole, indicated at 21, which is of less diameter than the pivot wire so that while the pivot wire cannot pass through it, the coned end portion can nevertheless pass up into it, as shown. Normally the elastic retaining orpressure plates 17 are flat as shown in Fig. 6. When one of them is screwed or forced down by the tightener or screw 19, its pressure is transmitted to the pivot wire, forcing or pressing the wire into the depression in the outer wall 16 of the slot 16, the dimensions and relationships of the parts being such that this pressure when the tightener 19 is fully screwed in is sufficient to hold the pivot wire against displacement but is not excessive, thus avoiding the danger of distortion of the wire or its support. By forcing the wire into engagement with the outer wall 16 the inner wall is left free from pressure, which pressure if it existed might result in closing the radial slots 3 more or less, which would cause the type bars to bind or be hampered in their free printing movements. In applying pressure to the wire as described the plate 17 will be bent slightly or will change its form, as clearly appears from Fig. 1. In practice the pivot wire is of such length as to extend something like of an inch above the top of the segment, and by reason of the engaging device or hole 21 in the plate 17 the pivot wire will assist in centering or floating the plate into its proper position when the screw 19 is somewhat loosened. The enlarged hole 18 affords a sufficiently free movement of the plate on the top of the segment to permit it to be properly located before the tightener 19 is screwed down into place. It will be understood that when it is desired to remove the wire for any purpose it is only necessary to loosen the tightener 19 to a sufficient extent to permit the plate 17 to be lifted out of contact with the pointed end 5 of the wire and swung to one side. In practice it is found that satisfactory results are obtained by holding one of the plates 17 (the right-hand plate for example, as shown in Fig. 2) in contact substantially along its entire under surface with the top of the segment by means of the tightener 19, this plate thus serving as a positive limiting stop for the fulcrum wire when it is pushed or thrust in from the opposite end into its slot. The right-hand plate having been secured and the right-hand end of the pivot wire having been brought into engagement with it as shown, the left-hand plate is brought into proper relationship with the left-hand projecting end of the wire, with the pointed end 5 engaging in the hole 21. Thereafter the tightener 19 is screwed down, its pressure being transmitted through the elastic element 17 to the crum wire, this pressure or tension causing the plate 17 to flex or bend, the amount of fiexure depending upon the amount of tension applied by the screw or tightener. The amount of pressure that can be applied 1s of course limited by reason of the fact that the tightener 19 is arrested at a defin te limit of movement by the pressure transmitting plate 17 after the latter has been finally stopped by the top of the segment'as shown in Fig. 1. Fig. 6 shows the condition of the plate before pressure is applied. thereto by the tightener. It has been found to be-not diflicult in practice o to proportion the parts as to provide a pressure on the wire 5 which while adequate can never exceed desirable limits. Thus harmful or excessive pressure applied to the pivot wire is surely prevented.

Various changes may be made without departing from my invention.

What I claim as new and desire to secure by Letters Patent, is

1. In a typewrlting machine, the combination of a type bar support, type bars, a pivot wire for said type bars, a pivot wire tightener, and an elastic element controlled by said tightener and effective on the end of said pivot wire to press it downward.

2. In a typewriting machine, the combi nation of a type bar support, type bars, a pivot wire therefor, a pivot wire tightener, and an elastic element effective through said tightener on said pivot wire, said tightener also serving to secure said elastic element to said support.

3. In a front strike typewriting machine, the combination of a vertical type bar segment, type bars, a pivot wire for said type bars, said type bars being mounted on said segment, pivot wire tightening devices comprising a threaded device, and a spring member controlled by said threaded device and operating on the end of said pivot wire to push downward against it.

4. In a front strike typewriting machine, the combination of a type bar support formed with an arcuate groove, a curved pivot wire seated in said groove, type bars on said pivot wire, a pivot wire tightener, and a plate controlled by said tightener and effective on the end of said pivot Wire to push said wire downward against the outer wall of said groove.

5. In a typewriting machine, the combination of a type bar support formed with an arcuate groove, a curved pivot wire seated in said groove, type bars on said pivot wire, a screw, and a spring member controlled by said screw and effective on the end of said pivot wire to push said wire downward against the outer wall of said groove, said screw also acting to secure said sprin member to said support.

6. n a typewriting machine, the combination of a type bar support, type bars, a pivot wire for said type bars, a plate supported on the type bar support and cooperating directly with the end of said pivot wire to hold it firmly in position, and means for varying the pressure exerted by said plate, said means also acting to secure said plate to said support.

Signed at Ilion, in the county of I-Ierkimer and State of New York, this 28th day of November, A. D. 1919.

GEORGE A. SEIB.

Witnesses:

LINNm F. BURNETT, ARMEDA KAPP. 

